Mains issues in Thailand

[Negativ3]

Hi forumers!

I have an odd mains issue (I think!)

Any appliance plugged in with a metal chassis gives a tickle to the user, be it a laptop or a microwave oven.

The house we live in has single phase and neutral (I think) coming in and I have checked the main fuse box and no main earth is evident. Every socket in every room is also 2-pin only. Every house on our street is wired the same way but I don't feel comfortable.

Can I sink a 3 meter copper rod into the earth to provide a local earthing or is this dodgy for us and/or the substation?

What can I check and measure to confirm if a fault exists?

Thanks

 

[trev]

Do a PIR it should reveal any internal wiring faults. As far as rodding it would contact with the local DNO be in order, they should be able to tell you if it'll be ok but an earth rod would be what I would consider.
Good luck mate

 

[timbobelfast]

Yes, Thailand's electrical installation has a lot to be desired!

For my pad out there I shipped out a Wylex CU and all the trimmings to fit. I wasn't happy with the Thai way. Most of my area are supplied via TT system so an earth rod was installed.
The Thai's tend to use that two core flex for everything which has about the same CSA as bell wire.

Also got the DNO out to install a pole to support the supply cables as a local guy had done it and as they neared the house they could be easily reached.

He had also installed a dodgy chinese rcd which would not have operated as there was no earth present!?!?

 

[Negativ3]

Thanks guys.

Seems like a real noob question however I have popped a couple of switch covers this morning and the wiring is not straightforward.

Black and white core colours are used and depending on the switch outlet, either colour could be wired to L.

With only these two cores available, is a Voltstick the best way to ID live?

 

[timbobelfast]

Black is the Line (Phase) conductor and White is the Neutral conductor. Polarity doesn't matter as your two pin plugs will operate no matter what way round they are plugged in to the socket face. Get some BS equipment shipped out to your location.

 

[Negativ3]

Ok, did a visual inspection as well as terminal tightness check and it all seems in order as far as I can tell. Any ideas what would cause a voltage to be present at metal enclosure parts? Is it just a lack of earthing that's the issue? Thanks.

 

[Mark42]

I'm just back from five years in Phuket and Kuala Lumpur. I built a house in the former, and shipped all the important parts from the UK. Local stuff is either rubbish, or a rip-off price.
The 'tingle' on the computer casings is due to earth leakage from switch-mode power supplies. Quite normal. Do what I did and install a local TT system. Ignore the DNO, waste of time.
Where are you in the 'land of smiles'? Yeah, right

 

[Negativ3]

I'm just back from five years in Phuket and Kuala Lumpur. I built a house in the former, and shipped all the important parts from the UK. Local stuff is either rubbish, or a rip-off price.
The 'tingle' on the computer casings is due to earth leakage from switch-mode power supplies. Quite normal. Do what I did and install a local TT system. Ignore the DNO, waste of time.
Where are you in the 'land of smiles'? Yeah, right

Thanks cash-and-dash,

I'm in Songkhla. When I get back from work I am going to install the earth conductor. Is it wise to install a suitably rated isolating transformer as well?

 

[Mark42]

Thanks cash-and-dash,

I'm in Songkhla. When I get back from work I am going to install the earth conductor. Is it wise to install a suitably rated isolating transformer as well?

You mean an isolating transformer to supply the computer? No, I don't think so, I've never heard of that being done - IT equipment needs an earth for the power supply to work properly. If it's isolated it would be earth-free. Maybe others on here could confirm - I'm not totally sure about this.

 

[needasparks]

is a Voltstick the best way to ID live?

I would think with wiring like you say everywhere in thailand a voltstick should be the last thing you use.
Can you possibly find better known earth/neutral source somewhere and even if you use an extension lead from that to everywhere as an earth reference to confirm polarity. Would love to see some pics of intake, these always make me smile on eastern installs.